<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link href="/static/bootstrap/bootstrap-3.3.7-dist/css/bootstrap.css" rel="stylesheet">
    <script src="/static/bootstrap/bootstrap-3.3.7-dist/js/bootstrap.js"></script>
    <script type="text/javascript" src="/static/js3/jQuery-2.1.4/jquery-2.1.4.min.js"></script>
    <style>
        .b{
            border: 1px green solid;
        }
    </style>
</head>
<body>
<div class="container-fluid">
<!--<div class="container-fluid b">-->
    <div class="row">
        <div class="col-md-8 b">.col-xs-12 .col-md-8</div>
        <div class="col-md-4 b">.col-xs-6 .col-md-4</div>
    </div>
    <div class="row">
        <div class=" col-md-4 b">.col-xs-6 .col-md-4</div>
        <div class=" col-md-4 b">.col-xs-6 .col-md-4</div>
        <div class=" col-md-4 b">.col-xs-6 .col-md-4</div>
    </div>
    <div class="row">
        <div class="col-xs-6 b">.col-xs-6</div>
        <div class="col-xs-6 b">.col-xs-6</div>
    </div>
</div>
<div class="row">
    <div class="col-md-4 b">.col-md-4</div>
    <div class="col-md-4 col-md-offset-4 b">.col-md-4 .col-md-offset-4</div>
</div>
<div class="row">
    <div class="col-sm-9 b">
        Level 1: .col-sm-9
        <div class="row">
            <div class="col-xs-8 col-sm-6 b">
                Level 2: .col-xs-8 .col-sm-6
            </div>
            <div class="col-xs-4 col-sm-6 b">
                Level 2: .col-xs-4 .col-sm-6
            </div>
        </div>
    </div>
</div>
</body>
</html>